Such water distribution systems have to meet various standards. First, it must, of course, be easily possible for the birds to obtain sufficient water. On the other hand, the system must be hygienic. There must be as little spillage of water as possible, since it is desirable for the litter used as a floor covering to remain as dry as possible. Moreover, the system should hinder the birds as little as possible, and the system should necessitate the fewest possible human actions for good functioning.
A number of water distribution systems are known in this field, and can be divided into various categories. A first category relates to the so-called bell-drinkers. In the case of such a system, which was developed particularly for turkeys, a number of drinking points are disposed around a central element, which is fed by means of a vertical supply line. A second category relates to a distribution system with long liquid lines, extending substantially over the entire length or breadth of a poultry house, each liquid line being provided with drinking points at regular intervals. The present invention relates to a water distribution system of this second category.
Various variants of embodiments have already been developed within this second category, each with their own advantages, but also shortcomings. In the case of a first variant each liquid line is in the form of a straight pipe, which is suspended at some distance above the floor and provided with drinking nipples on its underside. The height of the pipe relative to the floor is adjustable; as the birds grow, the height will be increased. The drinking nipples release a drop of water when they are touched. The idea is for a bird to drink the drops from such a nipple with its beak, the birds constantly knocking against the nipple, and new drops constantly being supplied.
A disadvantage here is that the drinking nipples are suspended rather high up for the birds, because the height of the straight pipe will be set in such a way that the birds can pass through virtually unhindered underneath the pipe. However, a bird wanting to drink then has to direct its beak upwards, which is an unnatural posture for the birds.
A further disadvantage is that the drinking nipples make the water available only in the form of a drop, and that a bird wanting to drink has to find a way of taking that drop from the nipple with its beak, which again is unnatural. In a natural way of drinking, a bird scoops water out of a water bath with its beak, in which case the water surface is situated at a lower level than its head.
It is a further disadvantage that the drinking nipples make only a small quantity of water available. The result is that it takes quite a long time before a bird has drunk a desired quantity of water. In addition, the drinking nipples are not suitable for providing several birds with adequate water simultaneously.
Furthermore, it is a disadvantage in the case of this system that quite a large quantity of water is lost in the form of drops falling onto the floor (spillage). In addition, the nipples also have to have drops when birds do not knock against the nipples, in order to let the birds see how they can come by drinking water; in other words, the nipples have to have a slight degree of leakage, so that drops also fall onto the floor when the birds are not drinking. The drops falling onto the floor lead to a damp patch in the floor covering below each drinking nipple. Such a damp patch gives rise to a risk of bacterial, viral and fungal infections. Moreover, droppings falling into such a damp patch will produce an increased emission of ammonia gas in the poultry house.
In order to counteract the problem of spillage, it is known to fit a drop collection tray below each nipple, which tray is fixed by means of a bracket to the liquid line. Although the spillage of water onto the floor is reduced by this, the drop collection tray is also a potential collection point for dust, dirt and microorganisms. Besides, the drop collection tray can hinder the birds when they are approaching the nipple.
A further drawback of this known variant is that the maximum output that can be supplied per nipple is relatively low, of the order of 0.1 litre/min. This is due to the fact that the pressure prevailing in the water line is relatively low, of the order of 30 cm rated water pressure, maximum approximately 50 cm water pressure.
In the case of a second variant there is also a horizontal main pipe, suspended at a distance above the floor, the height of suspension being variable. At each water-dispensing point, a branch line, running substantially in an L-shape, is connected to the horizontal main pipe. More particularly, such a branch line has a vertical pipe segment that is connected by its top end to the horizontal main pipe, and at its bottom end merges into a horizontal pipe segment. A drinking cup is placed at the free end of said horizontal pipe segment, on its top side. This variant has a number of important disadvantages.
The horizontal pipe segment generally runs parallel to the main pipe, so that the drinking cup is situated below the main pipe. This means that the headroom for the birds, i.e. the clear height above the drinking cups, is limited to the vertical distance between the drinking cups and the horizontal main line.
Another major disadvantage of this variant is the fact that the L-shaped branch line is difficult to clean. It is generally desirable for the water pipes to be flushed regularly. Various reasons can be given for this. First, it may be desirable, as already mentioned above, to place additives, such as medicines, in the water. On account of the low flow rate of the water in the lines, such additives can lead to deposits. It is further the case that bacteria and algae can grow in virtually stagnant water.
The horizontal main pipe is generally connected at one end to a water supply system, such as the water mains or a pump. The horizontal main pipe is shut off at its other end. The flushing is carried out by opening the shut-off valve at said other end of the horizontal main pipe, and possibly increasing the water pressure at the inlet of the horizontal main pipe, with the result that water flows at relatively great speed through the horizontal main pipe. However, the branch lines cannot be flushed in this way, because they are dead-end branches. It is possible per se to design the branch lines in such a way that they can be flushed, namely by placing a valve which can be shut off at the free end of the horizontal pipe segment of a branch line, beyond the drinking cup. In normal circumstances said valve is then closed; said valve is opened when the branch line is to be flushed. All said valves would, however, make the system relatively expensive. Moreover, it will be clear that opening and closing of all these valves is extremely labour-intensive.
A water distribution system according to the preamble of claim 1 is known from U.S. Pat. No. 4,341,182, in which FIG. 1 shows a main pipe extending in the horizontal direction with drinking cups fitted on top of it. At a slight distance above the drinking cups there is a suspension system for height-adjustable suspension of the main pipe. The suspension system here comprises a push rod extending in the horizontal direction and a pulling cable which is fitted above it and serves to prevent poultry from perching on the push rod.
A disadvantage of the water distribution system from U.S. Pat. No. 4,341,182 is that the headroom for the birds, i.e. the free height above the drinking cups, is limited to the vertical distance between the drinking cups and the horizontal main pipe. Another major disadvantage is that the birds are prevented by the horizontal main pipe from being able to pass through underneath the pipe.
The present invention aims to provide a new variant for such a water distribution system, in which the abovementioned drawbacks of earlier systems are eliminated, or at any rate considerably reduced.
More particularly, the present invention aims to provide a water distribution system that is multifunctional, in other words usable for different types of poultry, such as meat-producing poultry, ducks, turkeys, chickens, parent birds and laying hens, and is thereby suitable for providing birds with fresh drinking water from the first day (day-old chicks) up to the adult stage.
It is a further aim of the present invention to provide an improved water distribution system that has a high capacity.
It is a further aim of the present invention to provide an improved water distribution system that does not have any dead-end zones where water can remain stagnant for a long time thus enabling algae and bacteria to grow there, but a system which can be fully cleaned by flushing. More particularly, the present invention aims to provide a water distribution system which is free from dead-end branches.